Tartarus started life as the nephew of a venerable and religious pack leader known as Maccabeus on Doisac on July 8, 2491 and was a member of the Rh'tol skein.[5] He took on the childhood nickname of Tartar. Wearing the scarlet armor of a Jiralhanae Captain, the young Tartarus served as the security officer of his uncle's crew of one of the few Jiralhanae-controlled ships in the Covenant, Rapid Conversion.[6] The Sangheili did not approve of a Jiralhanae controlling a ship and had disabled many of its key features such as weaponry, gravity lifts, and other useful mechanics, but Maccabeus' faith in the Great Journey helped him turn a blind eye to this unfair treatment.[7]

Maccabeus summoned Tartarus at the pair's explosive arrival and would later become a protector of the Engineer when the resentful Yanme'e on board set out to kill it for taking their job: repair and maintenance of the vessel. He journeyed to Harvest during the first contact between the Jiralhanae and the humans, in a staged offer of peace that soon erupted into battle after an Unggoy, Yull, nervously attacked a member of Harvest's Colonial Militia. Tartarus proceeded to kill Yull by throwing him down cascades of water.[10] Later, Tartarus and Vorenus scouted out Harvest's orbiting platform Tiara. The two Jiralhanae remained at the station briefly, long enough to be sure that it was devoid of human life. They left Dadab in charge of sixty Unggoy on the station to protect it from human soldiers.[11]

On February 22, 2525, Tartarus participated in the siege of Gladsheim, serving as a gunner on a Type-25 Spirit. The Spirit was destroyed when several JOTUN cropdusters, controlled by the AIMack, were launched at the Spirit. Tartarus barely made it out alive, although he did not evacuate until he had tried everything to save the Spirit's pilot and young pack mate of his, Ritul, from the destruction. Ritul burned to death before Tartarus could save him.[12] When Tartarus, the injured Maccabeus, and others returned to the cruiser, they discovered that several Yanme'e that did not participate in the engagement were attempting to kill Lighter Than Some for "stealing" their engineering responsibilities. Vorenus and Tartarus attempted to defend the Huragok from the enraged Yanme'e and were eventually able to subdue them.[13]

Captain Ponder later managed to lure Tartarus, Vorenus, and two other Jiralhanae to the abandoned Utgard Mall using a false Oracle. As Rapid Conversion began to move over Tartarus' position, the colony's mass driver disabled the cruiser after two rounds and it crashed into Utgard. Furious over the trick, Tartarus killed Ponder and ordered Vorenus and the other Jiralhanae to disable the mass driver. Meanwhile, Tartarus returned to Rapid Conversion to confront his uncle.[14] After Tartarus returned to the crippled ship, he confronted Maccabeus about the legitimacy of their search for holy artifacts. Tartarus then challenged his uncle in the ritualistic manner of Jiralhanae to a fight to the death. He made concession to his wounded opponent by allowing Maccabeus to keep his weapon and removing the ammunition from his own. He successfully killed Maccabeus by taking his uncle's weapon, the Fist of Rukt, and smashing his skull. Through this fight, Tartarus began his ascent to the upper echelons of power.[9] Later during the battle on the Tiara above Harvest, Tartarus found Dadab dying from lack of methane. After saving the Unggoy, Tartarus revealed that he suspected him of aiding the humans and that he would allow Dadab to live long enough to explain the extent of his betrayal. Tartarus then killed the wounded Bapap, Dadab's friend.[15] As Tartarus charged into the fray, Dadab came to blame Tartarus for the deaths of his friends and the ongoing violence. As Tartarus battled Avery Johnson and the militia, Dadab came up behind the newly-crowned chieftain and shot him in the chest with an over-charged plasma pistol shot. Collapsing Tartarus' energy shielding, the chieftain killed Dadab and was then forced to flee the firefight.[16] In the following months, Tartarus and the crew managed to repair the Rapid Conversion and began to glass Harvest, eventually reducing the planet's surface to cinder.[17]

After the battle, Tartarus caught the eye of the High Prophet of Truth, who was attempting to replace the Sangheili with the Jiralhanae. Tartarus continued to gain more authority and soon controlled the majority of his skein. Truth and Tartarus would work together throughout the Human-Covenant War, and the Prophet of Truth eventually elevated Tartarus to a position that put him in control of all Jiralhanae forces in the entire Covenant military late in the war. The two continued to scheme, with Truth intending to make Tartarus the commander-in-chief of the entire Covenant military, and arm him and his Jiralhanae to lead a coup against the zealous Sangheili.[5][18] The meetings between Truth and Tartarus were kept a secret from the other Hierarchs, allegedly to prevent "petty jealousies".[19] Meanwhile, Truth accelerated production of Jiralhanae weaponry at Sacred Promissory and placed clans loyal to Tartarus' on valuable resource worlds.[1]

Even back before the Battle of Earth, the Prophet of Truth had trusted Tartarus enough to dismiss the Sangheili Honor Guardsmen—that never left the Prophets unprotected—in order to speak to him alone. Tartarus had scoured the wreckage of the Covenant attack coordination station Unyielding Hierophant after its destruction at the hands of the SPARTAN-IIs during Operation: FIRST STRIKE. Tartarus reported the Covenant fleet preparing to attack Earth was largely destroyed, and an artifact of the Forerunners that was able to bend time and disrupte slipstream space was almost entirely lost. The pilots had managed to recover three small chips of the crystal, (the rest of which were lost in slipspace after Corporal Locklear destroyed it with C-7 foaming explosives) which Tartarus presented to Truth.[20]

He was instructed to reward the surviving pilots well, then execute them all quietly to ensure Truth's plans remained secret from the rest of the Covenant. He was also ordered to bring Supreme CommanderThel 'Vadamee, who was unable to stop the destruction of Installation 04, before the Council to let "his fate match the magnitude of his failure." Tartarus branded the Commander with the Mark of Shame and took him to the Mausoleum of the Arbiter for his execution. When the Sangheili was pardoned and promoted to Arbiter, Tartarus was obviously displeased, but kept silent out of respect for the Prophets.[21] Tartarus provided aerial support for the Arbiter during his mission to assassinate Sesa 'Refumee on Threshold. The Arbiter encountered the Oracle during his duel with 'Refumee, and Tartarus quickly captured it and returned back to High Charity.[22]

Using information gained from the Oracle, the Prophets of Truth and Mercy sent the Arbiter and Tartarus on a mission to obtain the Sacred Icon on Installation 05. After dropping off the Arbiter in a Phantom, Tartarus had the dropship engage an Enforcer before it could kill the Arbiter. After the Arbiter disabled the containment shield, Tartarus arrived to pick him up in the Phantom, but was attacked by another Enforcer.[25] Later, while the Arbiter rode an anti-gravity gondola to reach the Library, Tartarus provided him air support against the attacking Flood. He also engaged the gondola that was ridden by the UNSC forces. When Tartarus entered the Library, he witnessed Commander Miranda Keyes engaged in a firefight with the Arbiter. Using the Fist of Rukt, he captured Keyes and took the index for himself. Tartarus and his Jiralhanae surrounded the wounded Arbiter, and the chieftain revealed that the Hierarchs had ordered him to betray and kill the Sangheili. Shocked at the revelation, the Arbiter was seemingly killed when Tartarus blasted him into an abyss. Tartarus then took Keyes and SgtMaj. Avery Johnson—as a Reclaimer was required to activate Delta Halo—and returned to High Charity.[24] At the same time, Tartarus' second-in-command, Melchus led the massacre on the Sangheili High Councilors.[26] Tartarus later commanded Covenant forces as the Great Schism broke out in High Charity when Sangheili warriors battled Covenant forces, while John-117 attempted to assassinate the remainder of the Covenant leadership.[27]

As the Flood began to infest the holy city, Tartarus and a group of Jiralhanae Honor Guardsmen escorted the High Prophets of Truth and Mercy to evacuation Phantoms, with Miranda and Johnson in tow. Tartarus ordered the humans to be split up into two different dropships. As Truth tasked Tartarus with activating Installation 05, the group was ambushed by Pod infectors. While Tartarus and the Jiralhanae guards succeeded in holding off most of the Flood, a single Pod infector managed to climb up along Tartarus' Fist of Rukt and latch onto Mercy's throat. Tartarus attempted to save the frail prophet, but Truth intervened and ordered that Mercy be left for dead. Tartarus reluctantly complied out of respect for Truth and carried on with his mission to activate Halo.[27] He chose Miranda Keyes to activate Delta Halo and then told the Jiralhanae under his command to kill the other human prisoners that had been accumulated over the course of the battle.[4]

While trying to get Commander Miranda Keyes to cooperate in the Control Room to activate the ring, Tartarus was confronted by the Arbiter and Sergeant Johnson. There was a brief stand-off in which the Arbiter asked 343 Guilty Spark about Halo's true purpose. The monitor explained that the rings were weapons of last resort built by the Forerunners to destroy potential Flood hosts. Guilty Spark also revealed that the Forerunners, having exhausted all other means of stopping the Flood, activated the Halo Array, destroying themselves along with all sentient life in the galaxy. The truth having been revealed, the Arbiter attempted to convince Tartarus of the Prophets' betrayal.[4]

Tartarus, however, remained blinded by loyalty to the Hierarchs and the promise of salvation, as well as his hatred for the Sangheili. He forced Keyes to unify the index with Installation 05's control panel activating the ring. Tartarus declared that the Jiralhanae, not the Sangheili, would be the escorts of the Prophets to the Divine Beyond. It was in this instant that Tartarus demonstrated a key difference between the Jiralhanae and the Sangheili, and one of the main reasons that the Prophet of Truth chose them to replace the Sangheili with the Jiralhanae. Truth knew that the Sangheili were more honorable and intelligent, and thus less easily manipulated. After learning the truth about Halo, Arbiter Thel 'Vadam turned against the Prophets. Tartarus, however, even after being presented with indisputable evidence of the Prophets' falseness, still chose to blindly follow them and activate Halo on their behalf. In the battle that followed, Tartarus used the Fist of Rukt to devastating effect, killing many of the attacking Sangheili. Eventually, the Jiralhanae Chieftain was brought down by the Arbiter after Johnson lowered Tartarus' shields with a beam rifle.[4]

Tartarus was easily recognized by his silver hair and fur, distinctive "mohawk" mane, and his use of the Fist of Rukt as his primary weapon. He was a powerful and aggressive leader who inspired both fear and respect in his subordinates. His devotion and faithfulness to the Covenant religion and the San'Shyuum (most notably the Prophet of Truth) was unwavering, but he nevertheless strongly represented the archetypal attitude of his entire race: rough, arrogant, and disdainful of the Sangheili. The Prophet of Clarity noted that he "radiated a sense of his own importance". He not only regarded himself as the chieftain of the entire Jiralhanae race, but as the leader of the entirety of the Covenant military. Although Tartarus generally disliked most species, he held some respect for the San'Shyuum, particularly the High Prophet of Truth. In fact, Clarity believed that only his belief in the Great Journey prevented Tartarus from using his hammer against other species in the Covenant.[19]

Tartarus was the nephew of Maccabeus, whom he killed on the bridge of Rapid Conversion in order to gain the position of Chieftain of his entire clan. Tartarus was very ambitious and impatient, as he desperately was wanting to set his plan with the Prophet of Truth into fruition.[23] Like most Jiralhanae, he sought to reach the top of his species' hierarchy, a goal he succeeded in.[5]

Despite his typically rude attitude, he was always polite and respectful when around the Prophet of Truth.[19] Tartarus was reluctant to leave the Prophet of Mercy for dead on High Charity, and only did so at the insistence of Truth.[27] Tartarus enjoyed a beverage that Truth reserved for high-ranking Jiralhanae. The drink was a thick, red, noxious liquid that was rumored to be toxic to other species.[28] Tartarus took great joy in using the Fist of Rukt, and the war hammer rarely left his side. Using the hammer to ensure obedience from the other species placed under his control, Tartarus would also use the hammer to eliminate any chieftain that attempted to challenge his command.[29]

Before he became Chieftain, Tartarus wielded the Type-25 Spiker with deadly force, with both its projectiles and fierce blades. Tartarus used an empty Carbine in his battle against his uncle Maccabeus. Eventually, he defeated Maccabeus and gained his new primary weapon, the Fist of Rukt.[9] He also made use of a variety of "invincibility shield" used by other Jiralhanae Chieftains, although his was longer lasting. In the battle between ArbiterThel 'Vadam during the Battle of Installation 05, only multiple direct hits from a beam rifle was able to penetrate his powerful shield. The shield quickly recharged, making Tartarus invincible once more. Even without his shield, Tartarus was still able to take enormous amounts of damage and take on disproportionate numbers of his Sangheili foes and kill many before succumbing to his injuries, a trait all Jiralhanae share.[4]

Tartarus was able to wield the Fist of Rukt with great strength, effortlessly eliminating foes in a single blow. By the time of the Great Schism, there were few individuals serving the Covenant that did not fear the sight of Tartarus and his hammer. After the hammer was upgraded by the High Prophet of Truth, Tartarus became an expert in operating the Fist of Rukt's newly attached fixed gravity impellors. He learned to not only use them to enhance the damage of the war hammer's attacks, but to also manipulate the gravity fields near and around opponents to his advantage.[29]

The Fist of Rukt was the personal weapon of Chieftain Tartarus. After he was given the title of Chieftain of the Jiralhanae, the High Prophet of Truth had the hammer modified with Covenant technology. Tartarus later carefully increased the hammer's haft to account for the upgrades added by the Covenant.[29] A heavily modified war hammer and the precursor to the Type-2 gravity hammer, the Fist of Rukt not only served as an excellent melee weapon, but could alter gravity to move objects and living beings around. The hammer was passed down from generations to generations in his family, by killing the current chieftain in a battle. Tartarus claimed ownership over the weapon after killing his own uncle, Maccabeus.[9] Tartarus wore little armor, aside from a heavy bandolier and a golden shoulder pad on his left arm, which he later attached what appears to be a Sangheili skull.[4]

Tartarus is the deepest part of the underworld in Greek mythology. It is a place of torment for the wicked, analogous to the Christian hell. The abyss is guarded by the three-headed "hellhound" known as Cerberus. Tartarus knocking the Arbiter into a deep abyss-like shaft may be an allusion to this namesake.

During the battle with Tartarus, he can sometimes be heard saying "Hammer time!", a reference to the popular catchphrase of rapper MC Hammer.

Despite using the Fist of Rukt left-handed during combat, Tartarus is seen wielding it in his right hand in most cutscenes.